Plans by the Iranian government to switch its citizens' internet to a domestic network to 'improve security' have been described as a deliberate attempt to control their access to the web.

Officials said the move will improve the country's protection against cyber attacks, but many Iranians believe it is the latest tactic to restrict and filter information online.

The announcement was made by a government deputy minister on Sunday and came as state television announced Google Inc's search engine and its email service would be blocked 'within a few hours'.

Vital communication tool: Dissidents in Iran have previously used social networks, like Twitter, to organise demonstrations (file picture)

In the televised announcement, an official - identified only by his last name, Khoramabadi - said: 'Google and Gmail will be filtered throughout the country until further notice.'

No further details were given.

The Google ban was thought to be connected to the anti-Islamic film posted on the company's YouTube site which has caused outrage throughout the Muslim world, according to the Iranian Students' News Agency (ISNA). However, there was no official confirmation of this.

Iran has one of the biggest Internet filters of any country in the world, preventing normal Iranians from accessing countless sites on the official grounds they are offensive or criminal.

Share this article

However, many Iranians believe the block on sites such as Facebook and YouTube is due to their use in anti-government protests after the disputed re-election of President Mahmoud Ahmadinejad in 2009.

Sites expressing views considered anti-government are also routinely blocked.

Virtual private network (VPN) software, which makes the computer appear as if it is based in another country, is commonly used by Iranians to overcome the government filter.

However, officials have long spoken of creating an Iranian Internet system which would be largely isolated from the World Wide Web.

Protesters march during a silent demonstration against the results of the 2009 Iranian presidential election in central Tehran. Dissidents used the internet to garner support

Blocked: An announcement on state television revealed filters on Google and Gmail in Iran 'until further notice'

Ali Hakim-Javadi, deputy communications and technology minister, said: 'In recent days, all governmental agencies and offices ... have been connected to the national information network.'

He added that the second phase of the plan would be to connect ordinary Iranians to the national network.

According to Iranian media, the domestic system would be fully implemented by March 2013 but it was not clear whether access to the global Internet would be cut once the Iranian system is rolled out.

Anti-government protests took place after the disputed re-election of President Mahmoud Ahmadinejad (pictured)

Even using VPNs, many Iranians suffered serious problems accessing email and social networking sites in February, ahead of parliamentary elections.

Cyber security was tightened by the Islamic Republic after its nuclear programme was attacked in 2010 by the Stuxnet computer worm, which caused centrifuges to fail at its main uranium enrichment facility.

Tehran, whose nuclear programme is suspected by the West of being aimed at developing a bomb, accused the United States and Israel of deploying the worm.

In April, authorities claimed a computer virus was detected inside the control systems of Kharg Island - which handles the vast majority of Iran's crude oil exports - but the terminal remained operational.

Last month Reza Taqipour, Iran's communications and technology minister, said Iran needed to develop its own network to ensure the safety of the country's information.

He added: 'Control over the Internet should not be in the hands of one or two countries. Especially on major issues and during crises, one cannot trust this network at all.'

In May, Iran threatened to take legal action against Google over its decision to drop the term 'Persian Gulf' from its Google Maps and leaving the waterway between Iran and the Arabian peninsula nameless.

Many Arab states refer to the sea as the 'Arabian Gulf', a term Iran considers unacceptable.

THE MOST POWERFUL COMMUNICATION TOOL AT DISSIDENTS' DISPOSAL: HOW THE INTERNET HELPED FUEL IRAN'S UPRISING

Iran is no stranger to internet censorship. In a country known for the oppression of its own people, fears over this latest move are, perhaps, unsurprising.

Earlier this year internet links were mysteriously cut - leaving millions without email and social network access - as rumours of planned anti-government protests circulated.

Gmail, Google and Yahoo were all thought to have been restricted and users were locked out of their online banking accounts.

For dissidents opposing the Islamic Republic's leadership, the internet has become one of the most powerful communication tools at their disposal.

Demonstrations have been orchestrated using blogs and social networks to gather support and increase numbers.

But, perhaps more importantly, the web has also been a crucial outlet for citizens to expose their oppression to the outside world.

Events that would have otherwise been shielded from Western eyes have been revealed to the international community, much to the anger of the government.

At no time has this been more obvious than during demonstrations in the wake of the 2009 elections, when thousands took to the streets to protest against the disputed victory of Iranian President Mahmoud Ahmadinejad.

As Iran played down events to outsiders, dissidents used Twitter, Facebook and YouTube to tell the world what was really happening.

The most shocking example of this was the death of music student Neda Agha Soltan, whose murder at the hands of a government militiaman was captured on a camera phone and uploaded to YouTube in 2009.

Millions watched horrific footage of the 26-year-old, who had been taking part in a peaceful protest in Tehran, as she was shot through the heart by a sniper and died minutes later in a pool of blood.